Because of their high printing speed and the advantageous neatness and clearness of the printed fonts and graphics, laser printers have become some of the most useful machines in modern, offices. However, in order to save office space and avoid incurring the cost of having to purchase multiplicity of printer machines, generally an operating laser printer is connected to and shared by several computers. The printed documents are output from the public laser printer and are accessible to the public at large in paper receiving bins. There is no provision to provide confidential protection for the printed documents. This setup is therefore not convenient nor pertinent to those documents which contain confidential information or secret characteristics.